As a global thirst for avocados shows no sign of slowing down, there's a darker side to everyone's favourite brunch choice.

"They're definitely problematic," says London chef Joseph Ryan. So much so, that when he opened up his vegetarian and vegan restaurant Wildflower in the increasingly hipster London neighbourhood of Peckham last month, he banned them from the menu – and not just because they've become basic.

"First of all, there's the cost issue – wholesale price has gone up 50 per cent in the last year," he explains. "Secondly, there's the carbon footprint and air miles issue. The whole ethos of our restaurant is about trying to reduce the carbon footprint of the ingredients, so why would I use an ingredient that's been flown in from 5000 miles away?"

Avocados are also a huge drain on water resources in arid countries – it takes approximately a bathtub of water to produce just one fruit.

Most disturbing for Ryan, though, is the fact that gangland violence has infiltrated production of avocados: "I find it highly troublesome that in Mexico, cartels are taking over the farms with fear and killings. Avocados are something that are becoming less and less sustainable, which is why we won't be serving them at Wildflower."

It will probably come as something of a shock to avid avo-fans that what's seen as a healthy, clean-eating choice in the UK is causing misery on the other side of the world. There's currently a shortfall in the massive demand for the fruit, known as "green gold" in South America, but more recently dubbed "blood avocados". In the state of Michoacán, which produces 92 per cent of Mexico's avocados, brutal cartels have inflicted torture, kidnappings and murder on producers as they seized control of the industry. Farmers are being harassed and extorted for their crops, as the cartels have moved from trafficking heroin and cocaine to avocados.

Of course, Ryan is not calling for a nationwide boycott of avocados – especially as this would only punish Mexican farmers further. He points out that you still can walk into pretty much any cafe in any hip city in the UK, and find avo toast on the menu, should you so wish. Wildflower leaving them off the menu is unlikely to make a dent in global production.

Thank you for the post. I lost my appetite for avocados on my last trip to the Bioreserve to see the butterflies. The avocado orchards are encroaching further up the mountain each year, it was sad to see.